The majority of double knit machines in existence today are fine gauge machines and more particularly 18 gauge machines. These machines were used to knit the majority of the double knit fabrics used in making slacks and trousers for ladies and gentlemen. But today many of these 18 gauge machines stand idle because of decreased demand for the fabric customarily produced on these machine.
Recently, there has appeared an apparatus utilizing a wheel for inlaying a yarn into fabric being knit on a double knit machine. See British Pat. No. 1,382,286 published Jan. 29, 1975. The inlay wheel in said British Patent comprises a shaft with a drive gear fixed to one end and a plurality of vanes fixed to the other end, each of which successively registers with the space between two adjacent needles in either the dial or cylinder bed, as desired. The drive gear has teeth which mesh with the stems or needles as the needle bed rotates in a conventional manner during knitting. Engagement of successive needle stems with the drive gear on the inlay wheel causes the inlay wheel to rotate on its shaft in the same direction as its associated needle bed and present successive vanes to the needle bed which register with the spaces between successive pairs of adjacent needles. The inlay yarn is trained circumferentially around successive vanes on one side of the inlay wheel and the vanes lay the inlay yarn on selected needles advanced to the tuck position and beneath other needles retained in welt position. The rotation of the inlay wheel delivers the inlay yarn to the needle bed and it is the correspondence in spacing of the gear teeth and the stems of the needles that causes the inlay wheel to rotate and deliver the inlay yarn to selected needles preparatory to being laid in the fabric.
Difficulty has been experienced in the use of the needle stems to rotate the inlay wheel because the critical correlation of spacing between the vanes and the spacing between needles in the needle bed is not reliably maintained; that is the rotation of the vanes on the inlay wheel is not reliably synchronized with the rotation of the dial. Consequently, the vanes sometimes hit the needles instead of meshing with the space between adjacent needles, causing a smash-up.
According to the invention, selected needles are removed (preferably alternate needles to half gauge the machine) to accommodate the inlay of coarse yarn, and the removed needles are replaced with drive elements which provide improved means to rotate the vanes of the inlay wheel in reliably precise synchronization with the rotation of the needle bed. The drive elements are of sturdier stock than the delicate needle stems used in the prior art to impart rotation to the drive gear and the drive elements are provided with butts so as to be under control of the needle cams but the drive elements do not have hooks or latches and play no part in knitting. The drive elements directly contact the vanes to impart rotational movement thereto as the needle bed rotates so that the separate gear of the prior art is eliminated.
The use of the inlay wheel in combination with the novel drive elements enables the production of a novel .[.two.]. .Iadd.fine .Iaddend.gauge ground or body yarn and the surface side is apparently formed of a heavy or coarse gauge yarn; although in reality the heavy yarn is laid in spaced courses and tightly locked in place by stitches of the ground yarn.